Automatic openable umbrella

ABSTRACT

The frame of a self-opening umbrella has a hollow shaft, a handle on one end of the shaft and a first ring fixed on the other end. A second ring slides along the shaft toward and away from the first ring and is biased away from the first ring by a helical compression spring in the shaft. A third ring slides on the shaft between the second ring and the handle. A first set of long ribs, normally carrying the cloth canopy of the umbrella, is pivoted to the first ring, and shorter second and third ribs are respectively pivoted to the second and third rings and connected to a common hinge on an associated first rib. The spring tends to open the umbrella, and the umbrella may be closed manually by pulling the third ring toward the handle and locking it in its umbrella closing position.

United States Patent [1 1 Murata AUTOMATIC OPENABLE UMBRELLA [75] inventor: Keiichi Murata, Daitoh-ku, Tokyo,

Japan [73] Assignee: Kabushiki Kaisha Ideal, Tokyo,

Japan 22 Filed: Dec.28, 1971 [21 Appl. No.: 212,904

[30] Foreign Application Priority Data 1/1963 Foltis et al. 135/22 6/1972 Sato l35/24 Primary ExaminerJ. Karl Bell Attorneyl(eeman and Berman [57] ABSTRACT The frame of a selfopening umbrella has a hollow shaft, a handle on one end of the shaft and a first ring fixed on the other end. A second ring slides along the shaft toward and away from the first ring and is biased away from the first ring by a helical compression spring in the shaft. A third ring slides on the shaft between the second ring and the handle. A first set of long ribs, normally carrying the cloth canopy of the umbrella, is pivoted to the first ring, and shorter second and third ribs are respectively pivoted to the second and third rings and connected to a common hinge on an associated first rib, The spring tends to open the umbrella, and the umbrella may be closed manually by pulling the third ring toward the handle and locking it in its umbrella closing position.

11 Claims, 8 Drawing Figures PAIENTEI] M1 7 sum 1 or 4 FIGJ INVENTOR Pmsmcum 1 ms 31146.025

SHEEI 2 0F 4 INVENTOR K Hc f/ 140mm BY I 4M PATENTEOJUU 1m SHEET 3 0F 4 IN VENTOR KEl/Chl 140K472} W M M M Pmamw m' I 3.746.025

SHEEI l 0? 4 I l 37a AUTOMATIC OPENABLE UMBRELLA This invention relates to umbrellas in which a cloth canopy can be spread out and tensioned by means of a frame, or collapsed by folding the frame, and particularly to a frame of a self-opening umbrella which may be locked in the closed position, and automatically opens when the locking mechanism is released.

Known self-opening umbrellas are provided with a conspicuous helical spring coiled about the shaft or rod. The spring is esthetically unsatisfactory and prevents the ribs of the frame from closely hugging the shaft in the closed condition of the umrella, thereby making the known umbrellas relatively thick when closed.

A primary object of the invention is the provision of an umbrella frame in which the spring necessary for biasing the frame toward the open position is practically invisible in the open umbrella, and which can be collapsed into a very slim package in the closed condition.

With this object and others in view, the invention provides an umbrella frame in which the shaft has an axially terminal portion formed with an axial bore. Three pivot rings are mounted on the shaft. One is arranged on the hollow terminal portion, the second pivot ring slides axially on the shaft between an umbrella closing position adjacent the first ring and an umbrella opening position spaced from the closing posi- I tion toward the other axially terminal portion of the shaft. The third pivot ring slides axially on the shaft between an umbrella opening position adjacent the second pivot ring and an umbrella closing position spaced from its umbrella opening position toward the other axially terminal shaft portion. Three sets of ribs are respectively pivoted to the three rings. Hinges connect each rib pivoted to the first ring to respective ribs of the two other sets in such a manner that the ribs on the first ring move angularly toward a closed position adjacent the shaft in response to movement of the third ring from the umbrella opening to the umbrella closing position, and the ribs on the first ring move angularly on the first pivot ring toward an open position remote from the shaft in response to movement of the second pivot ring into its umbrella opening position. A helical compression spring is contained in the axial bore of the shaft, and its two axially spaced ends are operatively connected to the first and second pivot rings respectively so as to bias the second ring away from the first ring and toward its'umbrella opening position. A releasable locking mechanism on the other terminal portion of the shaft permits the third pivot ring to be locked in its umbrella closing position.

Other features, additional objects, and many of the attendent advantages of this invention will readily be appreciated as the same becomes better understood by the following detailed description of preferred embodiments when considered in connection with the appended drawing in which:

FIG. 1 shows an umbrella frame of the invention in fragmentary elevation in the closed position;

FIG. 2 illustrates the frame of FIG. 1 in the opened condition;

FIGS. 3 and 4 are fragmentary, and partly sectional views on a larger scale of the devices of FIGS. 1 and 2 respectively; and

FIGS. 5 to 8 show a modified umbrella frame of the invention in views respectively corresponding to those of FIGS. 1 to 4.

Referring now to the drawing in detail, and initially to FIGS. 1 to 4, there is seen the tubular shaft 1 of an umbrella frame whose upper terminal portion, as viewed in the drawing, tapers toward a closed end. A ring 2 near the upper end provides pivots for the eight first or principal ribs 3 of the frame in a manner'conventional in itself, only one of the first ribs 3 and associated other ribs being shown in the drawing for the sake of clarity. As is best seen in FIGS. 3 and 4, the ring 2 is a radial flange fixed on the upper end of a cylindrical reinforcing sleeve 2a which coaxially envelops a portion of the shaft 1.

A second ring 4 similarly providing pivots for eight secondary ribs 5 slides freely on the sleeve 2a in the direction of the shaft axis, and a third pivot ring 6 carrying a set of third ribs 7 slides axially on the portion of the shaft 1 between the lower end of the sleeve 2a and a handle 8 on the lower, terminal shaft portion. The ribs 5 and 7 are approximately equal in length, and their free ends are hinged to a corresponding first rib 3 by a common pivot pin 3'.

A helical compression spring 9 is received in the axial bore of the shaft 1 between the closed upper end of the bore and a guide pin 10 passing diametrically through the second pivot ring 4. The pin 10 moves in aligned axial slots 11 of the sleeve 2a and 12 of the shaft 1. A stop ring or collar 13 carrying an annular buffer 14 of resilient material is fastened on the lower end of the sleeve 2a by means of a pin 15 which axially secures the collar 13 and the sleeve 2a on the shaft 1. The collar 13 limits the axial movement of the ring 4 in a direction away from the ring 2 under the biasing force of the spring 9.

A locking mechanism 16 on the lower terminal portion of the shaft 1 includes a leaf spring 17 secured in the axial bore of the shaft 1 in such a manner that a projection 18 on the spring 17 normally protrudes from a bore in the outer shaft surface. The free bottom end of the spring 17 is located in a bore of the handle 8 and carries a button 19 which normally projects radially from the handle 8. A knurled ring 21 is axially slidable on the upper end of the handle 8 toward and away from a position in which it axially projects from the handle.

As is best seen in FIG. 4, the pivot ring 6 is integral with a cylindrical sleeve which, as shown in FIG. 1, has an opening 20 located for alignment with the projection 18 and for entry of the projection into the opening 20 in the closed position of the umbrella frame seen in FIGS. 1 and 3. In that position of the frame, the second pivot ring 4 axially abuts against the first pivot ring 2, and the spring 9 is fully compressed. The third pivot ring sits on the lower terminal portion of the shaft 1 and is locked in its position by the projection 18. The primary ribs 3 are additionally secured by the knurled ring 18 which retains the free ends of the ribs 3 and prevents their angular movement on the pivot ring 2 away from the shaft 1.

When the ring 21 is lowered, and the button 19 is depressed by the user, the projection 18 is withdrawn from the opening 20, and the ring 6 is free to slide up ward on the shaft 1 toward the position seen in FIG. 2 in which it abuts against the underside of the collar 13, the movement of the ring 6 being brought about by the expanding spring'9 which moves the ring 4 into engagement-with the buffer 14, an intermediate position immediately preceding that of FIG. 2 being seen in FIG. 4. In the open position of the frame, the ribs 5 slope obliquely away from the closed end of the shaft 1 while the ribs 7 slope obliquely toward the same end to converge with the ribs at the pivot pins 3' which is axially intermediate the rings 2 and 4.

In the open position of the umbrella frame, the spring 9 is visible only through the narrow slots 11,12 in a portion of the shaft 1 which is not readily seen under the cloth canopy omitted from the drawing and normally attached to the first ribs 3 in a known manner, and is further obscured by the ribs 3,5,7. In the ciosed position of the frame, the ribs 3,5,7 can be folded toward the shaft 1 until they abuttingly engage each other and the shaft, and the non-illustrated cloth canopy can be folded and rolled tightly about the shaft and ribs into a very slim package capable of being inserted into a narrow tubular case, not shown, but commonly used.

The modified umbrella frame of the invention illustrated in FIGS. 5 to 8 has a tubular shaft 1 slightly larger in internal diameter than the afore-described shaft 1, but otherwise practically identical and carrying a locking mechanism 16 and a handle 8 at its lower end as described above. Three sets of ribs 3,5,7 are connected to the shaft 1' by rings 2', 4, and 6. A short tubular extension on the top of the ring 2 is attached to the shaft 1 by a diametrical pin 32 which also provides an abutment for a reinforcing tube 31 extending downward in the axial bore of the shaft at least over the range of movement of the pivot ring 4.

4 A diametrical guide pin 34 on the ring 4 moves in axial slots 35,36 of the shaft 1' and of the reinforcing tube 31, and its center is threadedly engaged by the reduced top portion of a rod 37. The enlarged bottom end 37a of the rod 37 provides an abutment for a helical compression spring 33 whose upper end engages the annular end face of the reinforcing tube 31, thereby holding the tube in engagement with the pin 32 on the first pivot ring 2' and biasing the second pivot ring 4 away from the first ring 2.

The movements of the rings 4,6 from the respective umbrella closing positions of FIG. 7 into the umbrella opening position of FIG. 8 under the biasing force of the spring 33 are limited by a coil spring 38 attached to the underside of the ring 4 and providing a resilient abutment for the ring 6.

The structural modifications described above do not materially affect the mode of operation. Both frames are opened by pushing the button 19 after release of the ribs 3 from the knurled ring 21, and are closed by pulling the third ring 6 toward the handle 8 until the projection 18 enters the opening 20 in the ring 6, and by thereafter securing the ribs 3 by means of the ring 21, if so desired.

The ribs 3,5 are channels of U-shaped cross section for greater stiffness as is conventional since they are stressed in compression and flexure during use of the umbrella. The third ribs 7 may be made of round wire since they are stressed in tension only, tensional forces being exerted by the user pulling the ring 6 toward the handle, and transmitted from the springs 9,33 by the ribs 5 and the hinge pins 3'.

The hinged connection between the ribs 3,5,7 may be modified without materially changing umbrella operation. The single hinge pin 3' may be replaced by two pins of which one connects either the rib 5 or the rib 7 to the first rib 3 whereas the second hinge pin connects the ribs 5,7 and may be spaced from the rib 3 in an obvious manner. The illustrated single hinge pin 3', however, is preferred.

The ultimate position of the third pivot ring 6 during the opening movement of the umbrella frame is not critical, and the ring does not require an abutment for limiting its upward movement. Means for limiting the downward movement of the second pivot ring 4 are helpful so as not to permit complete relaxation of the springs 9,33. It has been found beneficial to select the springs so that they cannot expand beyond a greatest length which is short by about 10 to 20 percent of their fully relaxed length so that their corresponding compressive stress effectively prevents collapse of the umbrella under wind pressure.

In each of the two disclosed embodiments, connecting elements are provided which connect the two ends of the springs 9, 33 to the rings providing pivots for the ribs 3 and the ribs 5 respectively in such a manner as to bias the pivot ring 4 for the ribs 5 from the umbrella closing toward the umbrella opening position.

The connecting elements for the upper end of the spring 9 in FIGS. l4 are constituted by the shaft 1 against whose inner, tapering wall the spring 9 abuts, and by the sleeve 20 which fixedly attaches the ring 2 to the shaft 1. The connecting element for the lower end of the spring 9 is the pin 10, fixed on the ring 4 and abuttingly engaged by the spring 9.

In the embodiment of FIGS. 5 to 8, the upper end of the spring 33 abuts against the lower annular end face of the reinforcing tube 31, the tube 31 is held in abutting engagement with the pin 32 by the spring 33, and the pin 32 is inserted in the ring 2, so that the tube 31 and the pin 32 provide a connection between the upper end of the spring 33, as viewed in FIGS. 7 and 8, and the pivot ring 2'.

The lower end of the spring 33 abuts against the enlarged bottom end 370 of the rod 37, and the reduced top end of the rod 37 threadedly engages the center of the guide pin 34 on the second pivot ring 4. The connection between the lower end of the spring" 33 and the ring 4 is thus formed by the rod 37 including its enlarged bottom end 370 and the guide pin 34.

While tubular metallic shafts 1,1' have been illustrated and are greatly preferred because of their mechanical strength at light weight, the shaft in an umbrella frame of the invention need not be provided with an axial bore over its entire length as long as the bore can accommodate the operating spring 9,33. The tubular reinforcing members 2a, 31 approximately double the effective wall thickness of the shafts 1,1' about the axial bore in the portion of the shaft which is axially coextensive with the stroke of the ring 4 and subjected to greatest stresses by the ring 4 under the biasing force of a spring 9,33. The reinforcing members thus permit the remainder of the shaft to be made relatively thin, and correspondingly light in weight.

It should be understood, of course, that the foregoing disclosure'relates only to preferred embodiments of the invention, and that it is intended to cover all changes and modifications of the examples of the invention herein chosen for the purpose of the disclosure which do not constitute departures from the spirit and scope of the invention set forth in the appended claims.

What is claimed is:

1. An umbrella frame comprising, in combination:

a. a shaft having a longitudinal axis,

1. a part of said shaft including one axially terminal portion thereof being formed with an axial bore;

b. first pivot means on said one terminal portion;

c. second pivot means axially slidable on said shaft between an umbrella closing position adjacent said first pivot means and an umbrella opening position spaced from said closing position toward the other axially terminal portion of said shaft;

d. third pivot means axially slidable on said shaft between an umbrella opening position adjacent said second pivot means and an umbrella closing position spaced from the umbrella opening position thereof toward said other axially terminal portion;

e. a first, a second, and a third set of ribs respectively pivoted to said first, second, and third pivot means,

f. a plurality of hinge means connecting each rib of said first set to respective ribs of said second and third sets for angular movement of said first ribs on said first pivot means toward a closed position adjacent said shaft in response to said movement of said third pivot means from said umbrella opening position into said umbrella closing position, and for angular movement of said first ribs on said first pivot means toward an open position remote from said shaft in response to movement of said second pivot means into said umbrella opening position thereof;

g. a helical compression spring in said axial bore and having two axially spaced ends;

connecting means operatively connecting said ends of said spring to said first and second pivot means respectively for biasing said second pivot means from said umbrella closing position toward said umbrella opening position thereof; and

. releasable locking means on said other terminal portion for locking said third pivot means in said umbrella closing position.

2. A frame as set forth in claim 1, wherein one of said first and second pivot means includes a pivot member, and said connecting means include a pin fastened to said pivot member and passing through said axial bore, one end of said spring being connected to said pin.

3. A frame as set forth in claim 2, wherein said one pivot means is said second pivot means, said pivot member is annular, said shaft is formed with two axially elongated slots, said pin extending substantially along a diameter of said pivot member and being guidingly received in said slots.

4. A frame as set forth in claim 3, wherein said connecting means include a rod member elongated in the direction of said axis, said spring being coiled about said rod member, respective longitudinally terminal portions of said rod member engaging said pin and said one end of said spring.

5. A frame as set forth in claim 1, further comprising a tubular reinforcing member substantially coaxial with said shaft and axially substantially coextensive with the stroke of said second pivot means between said positions thereof.

6. A frame as set forth in claim 5, wherein said reinforcing member is a sleeve on the outer face of said shaft, said second pivot means including an annular pivot member slidable on said sleeve.

7. A frame as set forth in claim 5, wherein said reinforcing member is received in said bore and has an annular end face, said spring having an end portion abuttingly engaging said end face, said reinforcing member being connected to one of said first and second pivot means for transmitting thereto the force of said spring.

8. A frame as set forth in claim 1, wherein said spring is under a compressive stress of at least 10 percent when said second pivot means is in said umbrella opening position thereof.

9. A frame as set forth in claim 1, further comprising means for limiting the movement of said second pivot means in the direction toward said umbrella opening position under the biasing force of said spring.

10. An umbrella as set forth in claim 1, wherein said second pivot means are contiguously adjacent said first pivot means insaid umbrella closing position.

11. An umbrella as set forth in claim 1, wherein said second ribs slope from said second pivot means obliquely away from said one axially terminal portion of said shaft in said umbrella closing position. 

1. An umbrella frame comprising, in combination: a. a shaft having a longitudinal axis,
 1. a part of said shaft including one axially terminal portion thereof being formed with an axial bore; b. first pivot means on said one terminal portion; c. second pivot means axially slidable on said shaft between an umbrella closing position adjacent said first pivot means and an umbrella opening position spaced from said closing position toward the other axially terminal portion of said shaft; d. third pivot means axially slidable on said shaft between an umbrella opening position adjacent said second pivot means and an umbrella closing position spaced from the umbrella opening position thereof toward said other axially terminal portion; e. a first, a second, and a third set of ribs respectively pivoted to said fIrst, second, and third pivot means, f. a plurality of hinge means connecting each rib of said first set to respective ribs of said second and third sets for angular movement of said first ribs on said first pivot means toward a closed position adjacent said shaft in response to said movement of said third pivot means from said umbrella opening position into said umbrella closing position, and for angular movement of said first ribs on said first pivot means toward an open position remote from said shaft in response to movement of said second pivot means into said umbrella opening position thereof; g. a helical compression spring in said axial bore and having two axially spaced ends; h. connecting means operatively connecting said ends of said spring to said first and second pivot means respectively for biasing said second pivot means from said umbrella closing position toward said umbrella opening position thereof; and i. releasable locking means on said other terminal portion for locking said third pivot means in said umbrella closing position.
 2. A frame as set forth in claim 1, wherein one of said first and second pivot means includes a pivot member, and said connecting means include a pin fastened to said pivot member and passing through said axial bore, one end of said spring being connected to said pin.
 3. A frame as set forth in claim 2, wherein said one pivot means is said second pivot means, said pivot member is annular, said shaft is formed with two axially elongated slots, said pin extending substantially along a diameter of said pivot member and being guidingly received in said slots.
 4. A frame as set forth in claim 3, wherein said connecting means include a rod member elongated in the direction of said axis, said spring being coiled about said rod member, respective longitudinally terminal portions of said rod member engaging said pin and said one end of said spring.
 5. A frame as set forth in claim 1, further comprising a tubular reinforcing member substantially coaxial with said shaft and axially substantially coextensive with the stroke of said second pivot means between said positions thereof.
 6. A frame as set forth in claim 5, wherein said reinforcing member is a sleeve on the outer face of said shaft, said second pivot means including an annular pivot member slidable on said sleeve.
 7. A frame as set forth in claim 5, wherein said reinforcing member is received in said bore and has an annular end face, said spring having an end portion abuttingly engaging said end face, said reinforcing member being connected to one of said first and second pivot means for transmitting thereto the force of said spring.
 8. A frame as set forth in claim 1, wherein said spring is under a compressive stress of at least 10 percent when said second pivot means is in said umbrella opening position thereof.
 9. A frame as set forth in claim 1, further comprising means for limiting the movement of said second pivot means in the direction toward said umbrella opening position under the biasing force of said spring.
 10. An umbrella as set forth in claim 1, wherein said second pivot means are contiguously adjacent said first pivot means in said umbrella closing position.
 11. An umbrella as set forth in claim 1, wherein said second ribs slope from said second pivot means obliquely away from said one axially terminal portion of said shaft in said umbrella closing position. 